Grinding-machine.



, B.1. BENGTSSON. enmnme MACHINE.

APPLICATION FILED SEPT. 15. 1915.

mama May 1, 1917.

neon some iamtersson, oriunmu m1), swmmn.

Gamma-Macrame.

Specification of Letters Patent.

, Application llled September 15, 1915. Serieli Io. 50,818.

Toall whom it may concern."

4313c iknown that I, Bnon 'JOHANNES Bimc'rssoN, engineer, a subject of the King (if Sweden, residing at Kallered, in the county of Gottenborg and Bohus and King dom of Sweden, have invented new and use ful Improvements in Grrinding-Machines,-v

of which the following is a specification.

provide a compendious an This invention relates totool grinding machines and particularly to hand operated machines, and has for its general object to easily operated device suited for eneral use, even by those not skilled in the andling of grinding machines, such as are commonly on the market. More-especially this invention has for its object toprovidc handy grinding machines which will occupy areduced space without afiectin .tltiegrinding power, thus renderlng themafa table for use anywhere, also to be broughthna bag, by workmen whohave to do their work at'a distance from their workshop proper.

Another object is to provide the grinding machine with tool rests or holders-which makes it easy for the laborer even if not skilled in the use, to grind knives, drills or other small tools with accuracy, including the angle of the point of spiral drills, which is always a rather difiicult job for unskilled people. 7

In carrying my invention into effect I em ploy a grinding wheel on a horizontal spine dle, rapidly rotated by means of a handle actuating a worm wheel with teeth arranged radiallyor nearly radially on the one side surface of the wheel, which teeth mesh with a worm attached to the spindle of the grinding wheel. The machine, further, is provided with means for attaching to it hold ers or tool rests which will enable tools of various characters to be readily treated by the machine and an accurate position, in relation to the grindin wheel, secured.

A structural embo iment of the invention is illustrated in the accompanying drawing which will now be clearly .described.

as in Fig.4, but viewed at riglp angles rotated at a high speed. '1

. ing Wheel p1 oper.

thereto; Fig. 6-is a cross-section through the drill holder with a drill therein and Fig. 7 a perspective view of the main parts of the drill holder xvhen separated and placed in, front of each other in such a position as they would in WC when ready to be connected.

The machi 1e consists-"in a'fr'ame or casing it with a 1humb screw '2 for clamping the machine in tle usual manner to a bench is or the like. In a bearingor hub portion F of the casing is rota'tably mounted a horizontal spindle i, which. at its iree end supports a toothed wheel ai'with' the teeth 9 arranged, on the one side surface in somewhat. the same manner. as on a beveltooth wheel, though the wheel may be of a cylindrical. and not a bevel shape. These radially or nearly re dially directed teeth '9: meslf with a worm c on a horizontal spindle 6, 1'0- tatable in s1 eves or bearings O, D in the casing h. A zcording to this invention and. as a consequznce of the described position 'of the teeth y the worm 0 is situated across actuating the wheel at and by reason of the worm gearing the grinding wheel a will be The tool tc be ground is placed on a table or tool rest t which is arranged so that itcan be adjusted to and from the grinding Patented May 1, 1917. j

wheel aby means of a set screw L and an open slot 10.

The machine is provided further with a special tool fest m for grinding knives 'or similar implements, such rest m being. pivote'd ona pi vot n in a bracket 0, which'is adjustable up and down in relation .to the grinding wheel by means of an open slot 11 and a set sclew 12. For the pivotable ad- 3usting of the rest m there is employed a set screw 3?, sore" ved through the rest and acting against a bracket 1" on the casing h. A prong 9 on each side of the rest m protects the rest from undue contacts with the grind- On eachs de of the grinding wheel the tool rest m is provided with a pair of balls 11.6

or otherwise rounded parts t, the two parts in each pair being situated above and directed toward eacl'rother and forming a guide or grip for the knife 8 that is to be treated in the machine and for that reason is placed with the edge between the parts 6. The

upper ball or part 2f in each pair can be pressed against the knifeby means of set screws 1), a2.

The described device makes it very easy even for an unskilled hand to grind a knife to an accurate angle along its whole edge, as

the workman only has to place the knife between the balls or parts t and to adjust the too]. rest on by means of set screws 12 and p to the desired position in relation to the grinding Wheel, after which he has merely to slide the'knife to and fro into the guide formed by the balls or parts 6;.

The machine is also 'PI'OYlClCll with a handy device for the grinding of drills,

which device comprises a holder of two parts The other part B of the holder consistsof a clamping dcvice for the drill. 4 to be treated and comprises two cheeks 1 and :2

each provided with a plurality of prismatic tceth 3 so arranged that they fit into each other, engaging around the drill when placed together as shown clearly in the Fig. 6. The two checks are rigidly held together in this position by means of a screw clamp 5 with'a thumb screw 13. The pa :t -B is provided with means which enable it to be pivotally titted to the part A in such a manner that the drill 4- rests with its point against the grinding periphery of the grind ing wheel a under precisely the angle required for its worli'ing edge, (,Fig. 4). .ln this position. the holder 13 can be oscilla ed, around the means which connects it to the part A, with the working edge.- of the drill remaining in contact with the'grnsling surface of the wheel (6 thus mak ng i possible to give the-drill the desired conical working surface.

To effect this it is necessary to employ two such pivotal fastening means arranged iisuch relation that the holder 15 can be shiftcd so as to treat the two opposite edges of the drill. The said means are'in the drawing illustrated as comprising cylindrical prongs 6, 7, one on each check 1 and 2 which prongs are inclined toward their respective cheeks in such a way, that when the cheeks are clamped together, the prongs t3, 7 stand at the same angle to eachother as the angle required for the drill (see'Fig. 4). Carried on the part A. there isa hub or sleeve 3 in which one of the prongs 6, 7 can be temporarily inserted and oscillated as described above. \Vhcn the one side of the drill is completed, the mentioned prong 6 (or 7) is removed from the sleeve y,'the part B turned over a half turn, and the other prong T (or (3) inserted into the sleeve y. Thus the accurate angle of the point .of the drill is secured.

Though I have described and illustrated th holder A-B comprising prongs 6 and 7 on the part B pivotable in a sleeve y inpart A, I do not limit myself to this special embodiment as these parts can'be varied in many ways without departing from the invention. For instance, theslecve y in part A may be replaced by pin, and the prongs .13, 7 in part B by sleeves, it being understood that the parts are arranged and s1t-' uated in such relation to each other that the clamp 15 can be pivotally mounted to the part A in a similar manner as stated above.

To facilitate the manipulation of thecl amp B when the drill is to be inserted be tweenor removed fromthe clamp B, the latter can be provided with some handy spring grip of any arbitrary shape, which is not illustrated in the drawing as it belongsnot tothe invention proper.

This'spring grip preferably may be of such& type that it permits the two checks 1 and 2 to be held, with the one hand, pressed together around the drill 4, while the other hand is free to screw or unscrew the clamping thumbscrew 13.

Having thus described my invention what I claim as new and desire to secure by'Eetters Patent is: i

1. In a grinding machine, the combination of a frame, 'a grinding wheel rotatably mounted thereon, a clamping device for holding a drill, projections on said clamp lng device disposed at thesame angl to each other as the angle required for the oint of the drill, and means on said frame rtr pivot-ally receiving said projections a1- ternativcly for the purpose set forth.

In a grinding machine, the combination of a frame, a grinding wheel rotatably 1 mounted t-her:-:,.-n, a clampingdevice,.-for holding a drill, a sleeve member ad uSt-ably mounted on said frame, a pair of cylindri- '(Jill PI'OJGClZlOHS on said clamp ng device arranged at substantially 90- to each other and each adapted to-rotatably engage in said sleeve for the purpose set forth.

3.. In a grinding machine, the combination of a frame,'a grinding wheel rotatably n'iounted th reon, a clamping device for holding a drill, and means for' adjustably supporting said clamping device upon said drill being on 01 posite jaws and on diamet- 10 frame, said clamping device comprising two rically opposite .lides of the drill. jaw members each having a plurality of In testimony whereof I afiix my signature 1}))i'isrnaticlgrippingftekeith adaptedl to (elngagle in presence of tn 0 Witnesses.

5 etween tie teet 1 0 t e other an sai teet 1 v e being cut away to form a central opening BROR JOE ANNES BENGTSSON' for the drill which is clamped therebetwe'en, Witnesses: and each pair of gripping teeth which lie GUSTAF Sm: in a common plane at right angles to the OLOF Lou's IiENNING. 

